An organic light-emitting device, such as an organic electroluminescent device (organic EL device), has been actively studied for enhancing the light emission efficiency thereof. In particular, various studies for enhancing the light-emitting efficiency have been made by newly developing and combining an electron transporting material, a hole transporting material, a light-emitting material and the like constituting an organic electroluminescent device. There are studies relating to an organic electroluminescent device utilizing a compound containing a carbazole structure and an indole structure, which are found among them, and some proposals have been made hitherto.
For example, PTL 1 describes the use of an organic compound having a carbazole structure and an indole structure represented by the following general formula, as a host material of a light-emitting layer of an organic light-emitting device. In the following general formula, m and n each represent an integer of from 1 to 5, provided that the sum of m and n is an integer of from 2 to 6; X represents an organic group having a valency of (m+n) which may have a substituent; and R1 to R14 represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group or a heterocyclic group.

PTL 2 describes the use of a compound having two or more carbazole structures, as a host material of a light-emitting layer of an organic light-emitting device. PTL 3 describes the use of a compound having two or more indole structures, as a host material of a light-emitting layer of an organic light-emitting device.